You can use installation media [a USB flash drive or DVD] to install a new copy of Windows, perform a clean installation, or reinstall Windows. To create installation media, go to the software download website, where you'll find step-by-step instructions. On that website, you can select a version of Windows and create your own installation media using either a USB flash drive
or a DVD. To go directly to one of the versions, select one of these links: Windows 7 Windows 8.1 Windows 10 [Then select Download tool now.] Windows 11 [Then select Download tool now.] To create the installation media, here's what you'll need: A PC with a reliable internet connection. The download time will vary, depending on your internet connection. A USB flash drive, external hard drive, or DVD. A blank USB flash drive or external hard drive with at least 8 GB of space, or a blank DVD [and DVD burner]. We recommend using a blank USB or blank DVD because any content on it will be deleted. When burning a DVD from an ISO file, if you're told the disc image file is too large, you'll need to
use dual layer [DL] DVD media. A product key. Your 25-character product key [not required for digital licenses]. For help finding it, go to Find your Windows product key. After you've created the installation media, you can reset or reinstall Windows. To learn more, go to Recovery options in Windows.
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Install Windows from a USB Flash Drive
- Article
- 11/09/2021
- 2 minutes to read
In this article
This topic covers how to manually create a Windows installation USB drive from Windows installation ISO disc image file or DVD, and is intended for PC manufacturers looking into creating media that they can use to manufacture Windows devices.
Tip
The steps described on this page assume you have Windows installation media and access to a Windows technician PC. If you're looking for an easy, automated way to create a bootable USB Windows installation drive, see:
- Download Windows 11
- Download Windows 10
What you need
- Windows installation media. This could be an installation .ISO or DVD
- USB flash drive with at least 5GB free space. This drive will be formatted, so make sure it doesn't have any important files on it.
- Technician PC - Windows PC that you'll use to format the USB flash drive
- Destination PC - A PC that you'll install Windows on
Step 1 - Format the drive and set the primary partition as active
Connect the USB flash drive to your technician PC.
Open Disk Management: Right-click on Start and choose Disk Management.
Format the partition: Right-click the USB drive partition and choose Format. Select the FAT32 file system to be able to boot either BIOS-based or UEFI-based PCs.
Set the partition as active: Right-click the USB drive partition and click Mark Partition as Active.
Note
If Mark Partition as Active isn't available, you can instead use diskpart to select the partition and mark it active.
Step 2 - Copy Windows Setup to the USB flash drive
Use File Explorer to copy and paste the entire contents of the Windows product DVD or ISO to the USB flash drive.
Optional: add an unattend file to automate the installation process. For more information, see Automate Windows Setup.
Step 3 - Install Windows to the new PC
Connect the USB flash drive to a new PC.
Turn on the PC and press the key that opens the boot-device selection menu for the computer, such as the Esc/F10/F12 keys. Select the option that boots the PC from the USB flash drive.
Windows Setup starts. Follow the instructions to install Windows.
Remove the USB flash drive.
If your Windows image is larger than 4GB
Windows USB install drives are formatted as FAT32, which has a 4GB filesize limit. If your image is larger than the filesize limit:
Copy everything except the Windows image file [sources\install.wim] to the USB drive [either drag and drop, or use this command, where D: is the mounted ISO and E: is the USB flash drive.]
robocopy D: E: /s /max:3800000000
Split the Windows image file into smaller files, and put the smaller files onto the USB drive:
Dism /Split-Image /ImageFile:D:\sources\install.wim /SWMFile:E:\sources\install.swm /FileSize:3800
Note
Windows Setup automatically installs from this file, so long as you name it install.swm.
Windows Setup Technical Reference